AU7647981A - Device in lawn mowers, leaf-collecting machines and the like - Google Patents

Description

Device in lawn mowers, leaf-collecting machines and the like

The present invention relates to a device in lawn mowers, leaf-collecting machines and the like, in which refuse material taken up from the surrounding ground is introduced into, and compacted in, a com- pacting device connected to the machine.

In connection with conventional lawn mowers and the like machines, the refuse material either is left on the mowed or treated ground or is transported by means of various apparatus, such as blowers, shovel devices or the like to collecting vessels of larger or minor volume. The refuse material which is very

3 3 voluminous, about 10 Kg/m - 20 Kg/m per volume of dry weight, requires frequently interruptions in the utilization of the machine for discharge of collected refuse material and big bulky collecting vessels and/or tips must be provided for the refuse.

To the end of reducing these problems it is known to provide compacting devices in connection with the machine which comprise a casing and various kinds of members, such as shovels, screws or the like for compacting the material within the casing. In these cases also, interruptions must be made for dis¬ charge of the compacted material from the casing. The main object of the invention is to provide a device in machines of the kind described hereinbefore, by means of which the collected refuse material is compacted continuously during operation of the machine so that the material is imparted, preferably in an adjustable manner, a volume weight which by 5-10 times or even more surpasses the volume weight o.f_. . the non-compacted material.

, Λ Another object is to provide a device of the said type with which the machine during a normal period of^'operation has not to be stopped in order to remove the collected material. Still an object is to provide a device of the said kind which permits- addition of composting chemicals to the compacted -refuse material.

These and other objects are obtained according to the invention by the compacting device comprising a compressing screw encased by a housing, within which the material is conveyed from an inlet under gradually increasing rate of compression to an out¬ let and a wrapping device connected to the outlet and within which the refuse material in its compacted state is introduced into a tubular wrapping which follows with the material, when this is forced out from the outlet. Other characteristic features of the invention become clear from the subsequent claims. The invention will below be described nearer in conjunction with the drawings. Fig. 1 shows a top plan view of a lawn mower, with its cover partly in section to show the compacting device according to the invention. Fig. 2 shows a front view of the lawn- mower of Fig. 1. Fig. 3 shows a longitudinal section through a preferred embodiment of the compacting screw according to the invention. Fig. 4 shows a side view similar to Fig. 3 of the invention applied to a leaf vacuum cleaner.

The lawn mower which in usual manner is provided with wheels, handles, control means etc., not denoted nearer, comprises a driving means, such as a motor 10. Disposed under the motor 10 is a cylindrical housing 22, shich surrounds a rotatable cutting blade 20 mounted on the motor shaft 12. A discharge duct 17 positioned tangentially inside the housing 22 is mounted relatively to the housing 22 and the cutting blade 20 so that cut-off or collected refuse material is slung by the centrifugal force from the rotating cutting blade 20 into the duct 17. The discharge duct 17 from the housing 22 opens into a conveyor and compacting screw disposed transversally to the duct 17, which screw, as will become clearer from Fig. 3, comprises a cylin- drical portion 36 and a conically tapered portion 37 with tapered outer and core diameters. The cylin¬ drical screw portion 36 is s-ur_rounded by a cylindrical housing 32 having perforations 30, whereas the conical screw portion 37 is surrounded by a conical housing 39 having perforations 31. The screw 36, 37 has at its left end, according to Fig. 3, a journal shaft 34 on which is mounted a sprocket wheel 13 which is driven via an endless gear chain 18 from a sprocket wheel 16 which is fixed on a by-shaft 14 driven by the motor shaft 12. Disposed in the compressing portion 37 of the screw is furthermore a sprocket wheel 38 penetrating through a slot into the housing 39 and which meshes with the threads of the conical screw portion 37 and is driven by the same. This sprocket wheel prevents the com- pressed refuse material from rotating with the screw 37 and ensures the axial advance thereof towards the outlet of the screw. The compressing screw portion 37 with housing 39 is preferably shaped so as to cause the volume between each screw thread and turn to be reduced so much that the material fed in from the cylindrical portion 36 of the screw has obtained a compression from 1:5 to 1:10 or more, preferably in the order of 1:8. The sprocket wheel 38 is encased in casing 33.

The refuse material propelled into the cylindrical screw housing 32 through the duct 17 by the rotation of the cutting blade or blades 20 impinges against the inner wall of the housing 32 and is retained therein, while air accompanying the refuse passes through the perforations 30 and in this way is separated from the refuse. Due to the refuse being continuously removed and advanced further by the conveyor and compacting

° screws 36, 37 the perforations are kept open and the blowing effect from the cutting blades 20 necessary for conveying the refuse material can be maintained undisturbed. By the compression of the refuse material in the compressing screw portion 37, there is in the treatment of moist or wet refuse a portion-of the accompanying water forced off and discharged through the perforations or holes 31.

Connected to the right-hand outlet end of the com- pacting screw portion 37, according to Fig. 3, is a

Hollow outlet stud 40 which has a cylindrical inner diameter or a diameter slightly increasing in the direction of feed. The inlet diameter of the tube 40 is, however, equal to the outlet diameter of the tubular screw housing 39, and the tube 40 has a length of about 2 to 3 times the inlet diameter thereof. Treaded onto the tube 40 is the refuse material re¬ ceiving wrapping 42 consisting of a flexible, hose¬ like tube or casing of paper, textile, plastic or like material, which is folded onto the outlet stud 40. The inner end of the wrapping or hose 42 may be pushed over a fixing flange, shown in Fig. 3, of the stud 40 and is retained by the same. Provided for receiving the filled wrapping tube 42 is a receiver and conveyor track 27 consisting of horizontally situated conveyor rollers 26 and vertically upstanding guide rollers 28 guiding the hose filled with compressed refuse material about the outer periphery of the lawn mower, as indi¬ cated in outline in Fig. 1. During the advancement of the refuse material by the tapered screw portion 37 the refuse is compressed in proportion to the gradually decreasing thread volume and with regard to the degree of charge in the screw portion 36, whereupon the refuse material in compressed state is introduced into the outlet stud 40 where it expands i.a. towards the cylindric inner surface of the tube. Thereby, a frictional resistance is created, which during the continuous transition of the material from the rotating screw portion 37 to the outlet stud 40 causes further compression of the material. This latter compression compensates for and equalizes possible variations in the ratio of compression in the screw portion 37 due to varying rate of charge. However, by exchanging the sprocket wheel 13, for example, the number of revolutions of the compacting screw 36, 37 can be adjusted to the type and volume per unit of weight of the treated refuse material. As mentioned, in the treatment of moist or wet refuse a portion of the water accompanying the refuse can be separated off through the perforations 31 by the compression of the material in the screw portion 37. This contributes to the reduction of the compressed refuse material and thereby facilitates the subsequent handling. The pressing-out of water has also an important effect in that case when the compressed refuse material is to be treated for composting pur- poses, as will be described herebelow.

Provided in the compacting screw 36, 37 is a bore 52 passing through the entire screw and terminating in an opening 50 at the outlet end of the tapered screw portion 37. Compost producing fluid or chemicals are fed into the bore 52 from a reservoir 60 located on a suitable place on the lawn mower and from which the fluid via a feed line 58 is supplied to a pump 56 and a line 54 which via a rotating coupling 55 is con¬ nected to the bore 52. In view of the dewatering de- scribed above of the refuse material in the screw portion 37 the chemicals added to the material at the bore opening 50 wil 1 not unnecessarily be diluted, and the concentration of chemicals required for the com¬ posting effect can be obtained with a lesser amount of added chemicals. The thus compacted and treated refuse material forms a plug or strand in the outlet stud 40. As the plug or strand is fed out from the stud 40, it tends to ex¬ pand and is then tightly enclosed by the previously described flexible wrapping hose 42 stored on the tubular stud 40. The filled wrapping hose, such as the plastic hose, is discharged axially from the tubular stud 40 into the previously described receiver-conveyor 27 where the hose is advanced continuously by the pro- pellant force of the screw 36, 37. When the advanced wrapped refuse strand has reached the far end of the receiver-conveyor 27, it can be severed at a distance of e.g.100 mm from the opening of the outlet stud 40 by means of a cutting device 43 positioned there, as is shown in Fig. 1. The compressed refuse strand entirely confined by the wrapping hose, such as the plastic hose, contains refuse material equivalent to ten times the volume of corresponding non-compacted material. With a diameter of the outlet stud 40 and the wrapping hose 42 on the order of 100 mm and a storage length of 2 m this is equivalent of a non-treated volume of about 100 to 150 liters, which in normal use of a lawn mower should eliminate totally the necessity for discharge during utilization in progress. The severed, wrapped strands of refuse can easily be formed according.to available refuse collection vessels or, if desired, be layered to become compost without the usual sanitary inconveniences, since the material is enclosed totally by the wrapping hose, such as the plastic hose, which upon completed composting process can be severed to desired lengths according to every requirement.

In the embodiment shown in Fig. 4, collection of the cut material is assisted or entirely achieved by means of a suction fan 61 connected via the duct 62 with a collecting chamber 63 surrounding the conveyor housing 32. The refuse material is sucked up into the housing 32 by the fan 61 via the vacuum duct 64. The description presented above relates to one embodiment only of the invention, and it is obvious that it can be varied and modified within the scope of the subsequent claims without departing from the aim of the invention.

Thus, the conveyor s.crew 36 may extend for its entire length through the conveyor housing without_., taper, as is shown in Fig. 4, whereby the compression takes place as the material is being forced by the screw 36 towards the outer end of the stud 40, whose diameter may then progressively descrease to a lesser degree.

Claims (10)

1. Device in lawn mowers, leaf-collecting machines and the like of the type, in which refuse material taken up from the surrounding ground is introduced into a compacting device connected to the machine, c h a r - a c t e r i z e d in that the compacting device com¬ prises a compressing screw^~(36, 37) encased by a housing (32, 39) within which the material is conveyed from an inlet under gradually increasing rate of compression to an outlet and a wrapping device (40) connected to the outlet and within which the refuse material in the compacted state is introduced into a tubular wrapping (42) which follows the material when this is forced out from the outlet.

2. Device according to claim 1, c h a r a c t e r - i z e d in that the screw comprises a cylindrical con¬ veyor portion (36) and a tapered, compressing portion (37), which has a ratio of compression between 1:5 and 1:10 and more, preferably about 1:8.

3. Device according to claim 1 or 2, c h a r - a c t e r i z e d in that the housing (32, 39) of the screw (36, 37) is provided with perforations (30, 31) of such magnitude that air and possible moisture accompanying the refuse material are evacuated from the material when this is conveyed through the housing.

4. Device according to any of the claims 1-3, c h a r a c t e i z e d by a rotatable toothed member (38) the teeth of which mesh with the threads of the compressing screw (37) and are driven by the same whereby the refuse material is prevented from rotating with the screw.

5. Device according to any of the claims 1-4, c h a r a c t e r i z e d in that the wrapping device comprises an outlet stud (40) connected to the com- pressing screw (36, 37) and constituting a carrier for the tubular wrapping (42) which preferably consists of a flexible hose of paper, textile or the like material.

6. Device according to claim 5, c h a r a c - t e r i z e d in that the outlet stud (40) in its longitudinal direction has the same inner diameter or a diameter slightly increasing towards the outlet end.

7. Device according to any of the claims 1-6, c h a r a c t e r i z e d in that connected to the wrapping device is a severing member (43) for cross- cutting of the tubular wrapping.

8. Device according to any of the claims 1-7, c h a r a c t e i z e d in that the compressing screw contains at least one bore (52) opening (at 50) at the outlet end of the screw (36, 37) and means (54, ' 55, 56, 58, 60) for supply of chemicals, such as a com¬ posting fluid, to said bore (52).

9. Device according to any of the claims 1-8, c h a r a c t e r i z e d by a receiving and conveying track (27) for the wrapped refuse material located behind the wrapping device (40) and comprising horizontal carrying rollers (26) and vertical guide rollers (28) for guiding the refuse material wrapped in tubular form about the periphery of the lawn mower.

10. Device according to any of the claims 1-9, c h a r a c t e r i z e d in that the inlet portion of the housing (32, 39) is connected to a suction device (61, 62) to create an air stream whereby material is taken up from the base to the compressing screw (36, 37).